针对强度调制和直接检测(IM-DD)短距光传输系统中,由于光器件带宽受限特性,导致接收端检测到的PAM4信号存在较大符号间干扰(inter symbol interference,ISI),给出了一种基于判决反馈均衡器(DFE)级联超奈奎斯特速率(FTN)传输的带宽受限...针对强度调制和直接检测(IM-DD)短距光传输系统中,由于光器件带宽受限特性,导致接收端检测到的PAM4信号存在较大符号间干扰(inter symbol interference,ISI),给出了一种基于判决反馈均衡器(DFE)级联超奈奎斯特速率(FTN)传输的带宽受限下的补偿方案,并在不同的带宽受限场景下进行了仿真验证。仿真结果表明,该带宽受限补偿方案能够有效地恢复接收到的PAM4信号,在误码率低于10-3时,有1 d B左右的性能收益。展开更多
A demodulator based on convolutional neural networks（ CNNs） is proposed to demodulate bipolar extended binary phase shifting keying（ EBPSK） signals transmitted at a faster-thanNyquist（ FTN） rate, solving the pro...A demodulator based on convolutional neural networks（ CNNs） is proposed to demodulate bipolar extended binary phase shifting keying（ EBPSK） signals transmitted at a faster-thanNyquist（ FTN） rate, solving the problem of severe inter symbol interference（ ISI） caused by FTN rate signals. With the characteristics of local connectivity, pooling and weight sharing,a six-layer CNNs structure is used to demodulate and eliminate ISI. The results showthat with the symbol rate of 1. 07 k Bd, the bandwidth of the band-pass filter（ BPF） in a transmitter of 1 k Hz and the changing number of carrier cycles in a symbol K = 5,10,15,28, the overall bit error ratio（ BER） performance of CNNs with single-symbol decision is superior to that with a doublesymbol united-decision. In addition, the BER performance of single-symbol decision is approximately 0. 5 d B better than that of the coherent demodulator while K equals the total number of carrier circles in a symbol, i. e., K = N = 28. With the symbol rate of 1. 07 k Bd, the bandwidth of BPF in a transmitter of 500 Hz and K = 5,10,15,28, the overall BER performance of CNNs with double-symbol united-decision is superior to those with single-symbol decision. Moreover, the double-symbol uniteddecision method is approximately 0. 5 to 1. 5 d B better than that of the coherent demodulator while K = N = 28. The demodulators based on CNNs successfully solve the serious ISI problems generated during the transmission of FTN rate bipolar EBPSK signals, which is beneficial for the improvement of spectrum efficiency.展开更多
文摘针对强度调制和直接检测(IM-DD)短距光传输系统中,由于光器件带宽受限特性,导致接收端检测到的PAM4信号存在较大符号间干扰(inter symbol interference,ISI),给出了一种基于判决反馈均衡器(DFE)级联超奈奎斯特速率(FTN)传输的带宽受限下的补偿方案,并在不同的带宽受限场景下进行了仿真验证。仿真结果表明,该带宽受限补偿方案能够有效地恢复接收到的PAM4信号,在误码率低于10-3时,有1 d B左右的性能收益。
基金The National Natural Science Foundation of China(No.6504000089)
文摘A demodulator based on convolutional neural networks（ CNNs） is proposed to demodulate bipolar extended binary phase shifting keying（ EBPSK） signals transmitted at a faster-thanNyquist（ FTN） rate, solving the problem of severe inter symbol interference（ ISI） caused by FTN rate signals. With the characteristics of local connectivity, pooling and weight sharing,a six-layer CNNs structure is used to demodulate and eliminate ISI. The results showthat with the symbol rate of 1. 07 k Bd, the bandwidth of the band-pass filter（ BPF） in a transmitter of 1 k Hz and the changing number of carrier cycles in a symbol K = 5,10,15,28, the overall bit error ratio（ BER） performance of CNNs with single-symbol decision is superior to that with a doublesymbol united-decision. In addition, the BER performance of single-symbol decision is approximately 0. 5 d B better than that of the coherent demodulator while K equals the total number of carrier circles in a symbol, i. e., K = N = 28. With the symbol rate of 1. 07 k Bd, the bandwidth of BPF in a transmitter of 500 Hz and K = 5,10,15,28, the overall BER performance of CNNs with double-symbol united-decision is superior to those with single-symbol decision. Moreover, the double-symbol uniteddecision method is approximately 0. 5 to 1. 5 d B better than that of the coherent demodulator while K = N = 28. The demodulators based on CNNs successfully solve the serious ISI problems generated during the transmission of FTN rate bipolar EBPSK signals, which is beneficial for the improvement of spectrum efficiency.
